Such a circuit breaker is described in Swiss patent application No. 4015/84-0 of Aug. 22, 1984. The known circuit breaker is provided with a housing filled with insulating gas and containing two contact members which are located in the interior of the housing and which can be moved relative to each other along one axis. To achieve a short constructional length, the power terminals of this circuit breaker enter diametrically with respect to the axis the interior of the housing and are there taken to the contact members transversely with respect to the axis. In this arrangement, a reliable transfer of power from the power terminal to the fixed contact member is achieved by two half-shells forming the fixed contact member and spaced apart from each other along a plane of separation, and by two flat bars arranged parallel to each other and brought to one of the two half-shells in each case as a power connection.